Anti-doming composition for a shadow-mask and processes for preparing the same

• US 6,094,003 A
• Filed: 10/21/1997
• Issued: 07/25/2000
• Est. Priority Date: 10/31/1996
• Status: Expired due to Fees

• Current Assignee: Samsung Display Devices Co., Ltd. (Samsung SDI Company Limited)
• Original Assignee: Samsung Display Devices Co., Ltd. (Samsung SDI Company Limited)
• Inventors: Rho, Hwan Chul, Han, Dong Hee, Moon, Sung-Hwan, Kim, Jae Myung
• Primary Examiner(s): Ramsey, Kenneth J.
• Application Number:
  US08/955,164
• Time in Patent Office: 1,008 Days
• Field of Search: 313/402, 106/626, 106/467, 106/618, 445/47
• US Class Current: 313/402
• CPC Class Codes: H01J 2229/0783 improving thermal radiation properties
• CPC Class Codes: H01J 29/07 Shadow masks for colour television tubes
• CPC Class Codes: H01J 9/146 Surface treatment, e.g. blackening, coating H01J9/144 takes precedence

Abstract

An anti-doming composition including a mixture of electron reflecting material such as bismuth oxide, and a zeolite, and a shadow-mask coated with the composition restrict temperature increase by preventing heat transfer, an anti-doming composition including lead and a ZnO, B₂ O₃, Bi₂ O₃ or a mixture thereof, and a shadow-mask coated with the composition protect mechanical expansion of a shadow-mask, and an anti-doming composition including ferroelectrics such as PZT, PT, PZ or PLZT, and a shadow-mask coated with the composition restrict temperature increase by changing the energy of electron beams into non-thermal energy. The shadow-mask of the present invention reduces about 30 to 50% of the anti-doming ratio and has a low production cost and easiness during processes.

Claims

1. A shadow mask comprising:

a steel layer having a plurality of holes for passing electron beams therethrough; and

a coating layer using an anti-doming composition comprising a vehicle selected from epoxy resins and butyl carbitol and at least one compound selected from the group consisting of PZT (PbZrTiO₃), PT (PbTiO₃), PZ (PbZrO₃) and PLZT [(PbLa)(ZrTi)O₃ ].

2. The shadow-mask as claimed in claim 1, wherein said coating layer is prepared by a silk screen printing method and has a thickness of 3 to 30 μ

m.

3. In a process for preparing a shadow-mask comprising the steps of preparing a steel layer having a plurality of holes for passing electron beams therethrough and coating an anti-doming composition to produce a coating layer on the steel layer, the improvement comprising:

said anti-doming composition includes at least one vehicle selected from the group consisting of epoxy resins and butyl carbitol and at least one compound selected from the group of PZT (PbZrTiO₃), PT (PbTiO₃), PZ (PbZrO₃), and PLZT [(PbLa)(ZrTi)O₃ ].

4. The process as claimed in claim 3, wherein said coating layer is prepared by a silk screen printing method and has a thickness of 3 to 30 μ

m.